The present invention relates to a fingerprint verification method for use in an access control system and more particularly to a fingerprint verification method which is fast, relatively inexpensive and has a low identification error rate.
Access control systems which use a fingerprint of an individual as the basis for verifying the identity of the individual have been proposed. These systems store an enrollment or reference fingerprint. Each time access is desired, a verification fingerprint scan is taken and compared to the enrollment or reference print. Based upon the comparison, access is granted or denied.
The fingerprint verification method used in the access control system must be capable of quickly and inexpensively comparing the verification scan to the reference fingerprint.
In many systems, it is essential that the system have a very low type I error. A type I error is the incorrect rejection of an individual seeking access. The installation may tolerate a somewhat higher type II error. Type II error is the incorrect admission of an individual seeking access. Nonetheless, it is also desirable to keep type II error low.
If the method used for comparing the input fingerprint and the file fingerprint involves the entire fingerprint, the result may be quite low in type I and type II errors but such a method tends to be too slow and too expensive for large scale control systems.
Accordingly, it is a purpose of the present invention to provide a fingerprint verification method having a very low incidence of type I error which operates at high speed and low cost.